Watching
by sebkurtofskyftw
Summary: Seblaine Kurt. Kinks: voyeurism, dirty talk, oral, non penetrative sex: intergluteal . Prompt: Kurt sees Seb and Blaine having sex and instead of being pissed, he gets aroused and watches them.


**Kinks**: voyeurism, dirty talk, oral, non penetrative sex.

**AN**: Written for factionb on tumblr. Enjoy!

Thank you for being my beta, Marianna! :)

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><p>Blaine looked beautiful.<p>

For once he didn't use a tube of hair gel and the disheveled bangs, damped with sweat, were glued to his forehead. Kurt watched him thoughtfully. His boyfriend's cheeks were flushed and lips parted. He was panting softly and clung to the other boy's jacket as if he would fall to the ground without that kind of support. They looked good together.

Kurt stood a couple feet away from the boy he loved, watching him in the embrace of someone else. The world should be falling apart around him at this very moment. He should be yelling, car-keying and throwing stuff. But somehow everything seemed distant and insignificant compared to the curve of Blaine's back and the clench of Sebastian's fingers.

Blaine cheated. Blaine was fucking cheating, now, with Kurt watching right there.

And yet Kurt couldn't pry his eyes away.

Sebastian's hand slid into Blaine's pants and groped his dick. Blaine tugged at Sebastian's hair, tilted his head on the side and sucked on the boy's earlobe. Kurt simply stared, frozen by the entrance to the common room. Sebastian and Blaine made out for a moment, standing there and swaying slightly in the air to an obscene dance, until Blaine gasped loudly and threw his had back.

"Oh, yes, my balls, yes."

The noise sent a shiver through Kurt and it was like a much needed shake that snapped him out of the haze. He looked around hurriedly and hid behind the pillar. He pressed his back to the wall and closed his eyes. Blaine was never this loud when they were together and somehow it was doing _things_ to Kurt. He opened his eyes and peeped out of his lair just in time to observe how Sebastian's hand drove deeper and Blaine's body tensed in his arms.

I should be going, Kurt thought. I need to go, right now.

Another gasp went through the air and Kurt pressed a palm to his groin. He caressed the growing erection and slid a hand into his jeans, until he reached the testicles. He tugged at them. The breath caught in his throat at the sensation and he repeated the motion. Sebastian's hand was still working in Blaine's pants. Kurt couldn't see well from this angle, but he tentatively moved his own hand further. His finger pressed to the point right behind his balls and...

OH.

_Oh._

"Did you hear it?" Blaine straightened up in Sebastian's embrace and scanned the room with a frown. Sebastian murmured something into Blaine's neck and soon the boy was too distraught to care about anything but the wet suction on his throat.

Apparently Sebastian got bored with making out after a while, because he pulled back and put a hand on Blaine's shoulders, pressing down. Blaine took the hint and dropped to his knees. Kurt slid to the floor as if his movements were coordinated with the other boy's. He groped his dick.

He would never have supposed he would react like that when being cheated on. But also, he had never been that turned on in his life and the perspective of stopping himself went out the window when Blaine unzipped Sebastian's pants and took his swollen cock out. Sebastian stared down at him and threaded his hand through the boy's hair. Blaine's mouth was right in front of his crotch, moist and red from their previous ministrations. Sebastian took a hold of Blaine's chin and brushed his thumb over the bottom lip. Blaine gave the head of a cock a slow lick and then slid the organ into his mouth easily.

"Oh yes. You take it so well." Sebastian said under his breath. "You're a natural, babe. Just look at you."

Kurt tugged his jeans down violently until they caught on his knees. He tried to push them further but his hands made their way onto his groins as if they had a separate mind. One of them came back to play with his balls, the other wrapped itself around the shaft tightly. Kurt bit his lips and stroked himself one time.

"You like it, don't you?" Sebastian murmured and Blaine moaned around the shaft in agreement. Kurt couldn't see Sebastian's face but he judged from the heavy breaths that he was enjoying it too. A lot.

Sebastian thrust into the boy slowly. Blaine withdraw and run his tongue along the shaft, then came back to sucking on the head.

Kurt's hand pumped his dick again and he suppressed a whine at the way Blaine was lapping at Sebastian's cock with an expression of utter bliss on his face.

"Oh you were born to do this, you little cocksucker. Now, give me that sweet ass of yours." Sebastian rasped out again and pushed at Blaine's shoulders, making him lay down on the floor. The boy looked confused for a moment, but Sebastian smiled down at him and kneed beside him. He patted his hip, giving him sight to turn around. When Blaine was on his four, Sebastian leaned over him and unzipped the boy's pants, kissing his neck at the same time. Blaine help him slid them down and Sebastian brought the head of his cock towards the hole and probed at it. Blaine turned his head around momentarily and gazed at him, surprised.

Kurt's hand stopped moving over his cock abruptly and he sat up straighter, watching the scene with wide eyes.

"I... We don't have... You need to..." Blaine stammered.

Kurt could swear he _heard_ Sebastian smirking. The boy rubbed his cock over Blaine's hole and slapped the left ass cheek hard. Blaine shuddered, whimpering. Sebastian ground his cock again and positioned it between Blaine's cheeks. Blaine's head dropped to the floor and rested there, temple pressed to the flooring. Sebastian spat in his hand and slicked the organ with the fluid, then he moved it tentatively over the butt crack. The sides of Blaine's cheeks gave a heavenly friction and he threw his head back, picking up the pace.

Kurt pressed a hand over his mouth to prevent himself from moaning. Blaine, on the contrary, was acting as if he was promised a prize for informing the whole Dalton Academy of just how good Sebastian's dick felt against his ass.

"...slut..." Sebastian chuckled.

Blaine didn't seem to mind the crude language, if anything it only made him push back. Kurt could see him jerking off ferociously and his own hand began to pump his cock harder and faster. He felt the release threatening to explode at any moment. Blaine moaned out Sebastian's name loudly and Kurt didn't have any time to wonder how come no one had walked on them yet, because Sebastian stilled, grabbed his cock into his hand and shot white spurts of cum on Blaine's ass. The sperm dripped down the ass cheeks as the boy slid down on the floor boneless, and laid beside Blaine, panting heavily. He kissed Blaine's forehead tenderly and Kurt felt a cold pang in his chest, but soon all his thoughts liquefied into blackness and he came hard all over his hand, his lips parted in a soundless scream.

The boys laid there for a moment, oblivious to the world around them. Sebastian stood up first and reached a hand out to help Blaine get up. Blaine murmured something and Sebastian burst out laughing.

Kurt awkwardly wiped the cum on his jeans, pulled them up and sat back down, pressed to the wall. He wrapped his arms around himself and watched Sebastian and Blaine. They cleaned themselves up carelessly and walked out the other door, Blaine leaning on Sebastian's side.


End file.
